What are the main bird threats?
According to the International Union for Conservation of Nature (IUCN) at least 12% of the world’s bird species—between 9,800 and 10,400 depending on the taxonomic classification methods—are threatened with extinction, and an additional 8% are near threatened.
What this means is that, conservatively, one of every five bird species could be extinct in the next 50-80 years which equates to more than 2,000 species! Though the reasons for this are varied, the overwhelming culprit is habitat degradation via agricultural development and human population growth.
Bycatch of seabirds in fisheries operations occurs primarily when albatrosses and petrels are accidentally hooked during long-line deployment or when diving birds like auklets or murres became entangled in gill or trawl nets though it is the former which produces the vast majority of seabird mortalities.
While considerable steps have been taken to decrease the incidence of these mortalities, it is estimated that at least 37 species of seabirds are somehow at risk from fisheries operations, and 22 of these are seriously threatened especially in the Southern Latitudes.
Deforestation occurs via logging or burning, and there are four main motives that fuel the chainsaws and stoke the fires: wood for fuel usage, lumber for construction, land clearance for plantation or ranch development, and urban expansion. Forests provide vital shelter and nesting structures and a bounty of food.
What perhaps is not evident, particularly to those living in the developed regions whose landscapes were long ago altered, is that forest loss in the tropical latitudes is occurring at incredible rates.
At least 5 billion pounds of pesticides are manufactured each year; 20% is used within the United States or Western Europe. Per capita, the most frequent users of pesticides are the monoculture farms of Central America, (such as banana plantations) as well as the large producers of cereal grains and fruit in Brazil, the US, and France.
Common ways in which pesticides damage bird populations are death by exposure from a concentrated dose, bioaccumulation (fat-soluble chemicals increase in concentration with every step up the food chain), hormonal effects, and fewer or weaker eggs. They can also destroy of prey organisms and damage plants used by birds for feeding, roosting, and nesting.
Non-native predators (e.g. rats, snakes) are quite common on many islands which birds utilize for safe nesting grounds. Toxic contaminants are also sometimes prevalent both on islands (e.g. lead paint chips) and at-sea (small colorful plastics which they mistake for food items and which can, at the very least, considerably inhibit their digestive processes).
Want to learn about bird conservation, and what people are doing to brighten their futures, click here.